Ball and socket joints



I March 3, 1959 I J. LATZEN BALL AND SOCKET JOINTS 7 Filed Dec. 27, 1954 e Sheets-Sheet 1 lnvenl'or March 3, 19 59 7 J. LATZEIQ BALL AND SOCKET JOINTS Filed Dec. 27, 1954 6 Sheets-Sheet 2 March 3, 1959 Filed Dec. 27, 1954 J.LATZEN BALL AND SOCKET JOINTS 6 Sheets-Sheet 3 s Sheets-Sheet 4 J. LATZEN BALL AND SOCKET JOINTS N E M March 3,1959 J. LATZEN 2,876,029

BALL ANDY SOCKET JOINTS Filed D ec. 27, 1954 e Sheets-Sheet 5 Fig. 12 25 V ////M "*f'T'iT 35 In van/or Josef LA TZ E N I March 3, 19 59 JQLATZEN.

BALL AND SOCKET JOINTS Filed Dec. 27,1954 4 6 sh m-sheets W WA I In vn/'orf: Josef LATZE/V aw-www United States Patent 8 Claims. (Cl. 287-90) Claims priority,

The invention relates to a ball and socket joint, for example for the steering linkages of motor vehicles, but without being limited thereto, in which the ball. end or head of a joint pin is mounted in a hollow joint housing with an internal spherical surface and provides a ball and socket joint which can be produced extremely simply and cheaply, and which has a long working life and requires little attention.

The known ball and socket joints usually comprise a steel. socket with a stud or lug for connection to the steering linkage, and also a steel joint pin with aball end which is mounted in a hollow spherical housing. In this case, it is possible to form the internal spherical bearing surface directly by means of the joint socket or by means of special inserted elements. According to proposals which have not been published, it is possible, in these joints, to provide inserted elements made of synthetic resins of greater or lesser elasticity depending on the properties required and on the purpose of the joint. Sockets may be lined with, or ball ends covered with such synthetic resins to form the surfaces sliding 'on ormoving against one another.

way, they are nevertheless rather costly owing to the relatively large consumption of steel and the necessary working and treatment thereof.

. amides and superpolyamides, in particular polycondensation products of adipic acid and hexamethylene diamine, polyurethane or of glycol polyester reacted with diisocyanates, particularly naphthalene diisocyanates, and, if required, the synthetic resin is provided with a reinforcement, for example metal inserts, a metal casing or the like. Thus, whereas according to previous proposals synthetic resin, in its use in ball and socket joints, constitutes only an aid or supplementary means for forming surfaces having special properties and for obtaining elasticity, according to the invention synthetic resin essentially forms the joint and ferrous or non-ferrous metal materials are only aids.

Preferably, synthetic resin formed as a product of glycol polyester reacted with diisocyanates, particularly naphthalene diisocyanates, is used for forming the socket. This synthetic resin is distinguished by its great elasticity, its resistance to abrasion, resistance to wear and low frictional properties.

According to the invention, it is also possible to form the socket from layers of synthetic resins of difierent properties, the layers being cemented together. Thus, for example, the bearing surface of the socket can be formed by a layer of synthetic resin produced by the reaction of glycol polyester with diisocyanates, while the remaining part of the housing consists of less elastic synthetic resin, in particular ofthe types mentioned. In

Although the prop- 'erties of ball and socket joints can be improved in this this way a housing can be produced which has an elasticity decreasing from'the inside towards the outside so in the external zones, while the internal bearing surface has the elasticity of rubber.

It is also possible for special elements for forming the bearing surfaces'to be inserted in a socket formed of synthetic resin, the inserted elements being made, for example, of ferrous or non-ferrous metal. The combination of the synthetic resin with fabric, which may be impregnated with synthetic resin, and also with rubber, is similarly possible.

To reinforce the synthetic resin, a cup-like ring may be embedded in the lower part of the. socket. This cuplike ring may be formed by arms extending from a member which connects the housing to the In this way, the reinforcement of the synthetic resin also forms the connection with the linkage. Reinforcement for the synthetic resin formed of flatsectional material may be provided with perforations and/ or recesses for the entry or penetration of the synthetic resin, so that the reinforcement is firmly anchored in the resin.

If the socket consists of elastic synthetic resin, for example synthetic resin having the elasticity of rubber, then it is preferable to close the opening in the side of the socket opposite the joint pin by means of a cover to ensure that the socket bears on the ball end. For this purpose, for example, the opening in the socket may be provided with an internal groove and the cover is in the form of a metal plate curved to correspond with the surface of the ball 'end and provided with a bent rim which engages and fills the groove. In this case, the internal groove may also have a ridge formed on its outer edge behind which the rim of the cover may engage. Of course, it is also possible to place a cap, if desired in addition to the cover plate, over the opening in the socket. v

In a housing having the elasticity of rubber it is possible to insert the joint pin through the opening in the side of the socket opposite that from which the pin extends, the ball end snapping into the socket. In this way, considerable simplifications and reduction in cost are achieved in the assembly of the joint.

The socket made of synthetic resin may advantageously engage in the manner of a plug in the steering linkage and embrace the latter. This afiords the advantage of a safe connectionwith the steering linkage at the point where the steering forces act on the joint socket, so that this point does not constitute a special danger point.

Another type of reinforcement for, the synthetic resin housing may consist of wire stirrups or loops which are disposed in the circumferential direction of the housing and which are embedded in the synthetic resin above and below a plane through the centre of the ball end transversely of the axis of the joint pin. These wire stirrups preferably extend into the plug portion of the socket engaging in the steeringlinkage.

Preferably, the synthetic resin socket may be surrounded except on the side opposite that from which the joint pin extends by a thin-walled metal shell or a sheet metal cup, which is connected to the steering linkage through arms. 7 I

A further possibility for forming a shell covering the socket consists in that a tubular linkage member is provided with an opening in a'directio-n transverse of its axis and is expanded at the section where the opening is located to a size determined by the size of the socket to be formed and the synthetic resin forming the housing for the ball end of the joint pin is introduced into the expanded opening and the part of the tubular linkage member adjacent thereto. In this case, the walls of the linkage member covering the synthetic resin may have perforations, recesses or the like for the entry or penetration of synthetic resin in order to effect a firm anchorthat it is rigid Patented Mar. 3, 9,

steering linkage.

bedded in the synthetic resin.

surfaces sliding over one'another for example, the surface of the ball end, is of an unsmoothed nature. and exhibits relatively fine resin being the product of glycol polyester reacted with diisocyanates. The surface, which is reminiscent'of wrinkled or finely grained skin, may be made of steel or. a nonferrous metal. The bearing surfaceiof the socketmay also be of the same character. Similarly" two synthetic resin surfaces whichco-operate and which may consist of synthetic resin of dilferent types may be of the same character. Surprisingly, it has been found that a surface of such a-character in conjunction with the preferred elastic synthetic resimprovides particularly good sliding properties and has a wearpreventing action. A film of oil is distributed particularly favourably, because the surface has, so to speak, holding pores to receive it. Furthermore, fine and very fine dirt particles, which. otherwise have such a deleteriousetfect in ball and socket joints, may be allowed to escape in addition to the possibility of becoming em- The necessity for accurate working or machining of the joint is considerably reduced; since, for'example, an accurate, moulded ball can be used in the socket without any further finishing treatment and yet better sliding properties and wear resistances are obtained.

' The unsmoothed surface can also be provided by forming on it fine ridges or corrugations. Similarly, the insertion or embedding of more or less finely corrugated synthetic resin foils of appropriate thickness is possible for obtaining the desired surface nature. Fine corrugations can also be formed in the surfaces, which are covered with athin foil ofsynthetic resin. The surfaces sliding on one another may also. be blasted with shot or pellets to producea surface character having said properties. this case, compression of the sliding surfaces is also simultaneously produced. Compressed or compacted sliding surfaces of this nature may also be covered with a'thin foil made of synthetic resin being the product of glycol polyester reacted with diisocyanates.- The character of thecompressed surface is imparted to the surface of the covering. 7 V

Various examples of embodiments of the invention, without however limiting the-invention to these examples, are shown in the accompanying drawings in which: Fig. 1 is a vertical sectionon the centre line of a joint according to the invention;

Fig. 2 is a horizontal section of the joint shown in Fig. 1;

Fig. 3 is a half vertical section at right angles to the section shown in Fig. 1;

Figs. 4, 5 and 6 are similar to Figs. 1, 2 and 3 but showing a modification to the joint;

Fig. 7 is a vertical section showing a further modification; 7

Figs. 8, 9 and 10 are vertical and horizontal sections of a still further modification;

Fig."11 is a perspective view of a shell for enclosing the joint shown in Figs. 8, 9 and 10;

' Fig. 12 is a vertical section on the centre line of another joint according to the invention;

Fig. 13 is a part horizontal section of the joint shown in Fig. 12;

Fig. 14 is a vertical tion shown in Fig. 13; v Fig. 15 is a vertical section showing a modification to the joint shown in Figs. 12-14;

section at right angles to the sec- ,poured in Fig. 16 is a vertical section on the centre line of another joint according to the invention.

In the ball and socket joint of which diiferent sections are shown in Figures 1 to 3, the joint socket 1 consists of synthetic resin being a product of glycol polyester reacted with diisocyanates, in which a steel cup ring 2 is embedded. The tubular connecting member 3 is forked and the arms of the fork are bent round to form the also embraces the tubular connecting member at 6. In the cup ring perforations 7 are provided into which the synthetic resin penetrates. The socket is closed by a sheet metal cover 8, the upwardly bent over edge 9 of which engages in an internal groove 10 around the forced apart after the joint has been assembled. On the side fromwhich the joint pin 12 extends the synthetic resin socket is provided with an annular lip 11 which lies closely against the neck 13 of the pin. The pin neck may also be of reduced diameter as is indicated in Fig. 1 in chain dotted lines.

embedded in the socket in the circumferential direction, are provided instead of a reinforcing cup ring 2. One wire stirrup 14 is located above a plane taken through the centre of the ball end transversely of the axis of the joint pin 12 and the other stirrup 15 is embedded below said plane. The stirrups extend into the linkage connection member 16 and pass through holes therein. The ends of said stirrups may be welded together where they abut. Similarly, the stirrups may be welded or connected in any other suitable manner to the connecting member 16. In production of the socket, the synthetic resin is cast around the stirrups and a part of the linkage connection member. In this example of embodiment also, the socket is provided with an annular lip which bears against the neck of the joint pin, while in the example 'of embodiment according to Fig. 7 a special packing sleeve 17, which consists of highly elastic synthetic resin is provided.

The example of embodiment shown in Figs. 8 to 10 discloses a ball and socket joint the socket 18 of which consists of synthetic resin selected from the class of the polyamides or superpolyamides and has an internal lining 19made of synthetic resin being a product of glycol polyester reacted with diisocyanates. The reinforcement of thesocket is similar to the reinforcement according to the example of the embodiment shown in Figs. 1 to 3. In addition to this reinforcement, an external cup or shell 20 of sheet metal may also be provided, the arms 21 of which are secured to the linkageconnection member by spot welding, for example. Sealing is effected by means of a special sleeve 17 made of highly elastic synthetic resin. The'shell 20 is shown' separately in Fig. 11 in perspective View.

Figs. 12 to 14 show an example of embodiment in which a tubular connecting member 22 forming part of a steering linkage is provided with an opening 23 transof its axis. At the transversely apertured portion tubular member is expanded to the size of the joint housing to be formed. The elastic synthetic material 25, in the present case synthetic resin being the product of glycol polyester reacted cup-shapedplates 26, which may be welded in. elastic sleeve 27 is provided as the seal for the exit the joint pin 12 from the joint socket.

In the example of embodiment according to Fig. 15,

for

he elastic synthetic resin housing comprises an aniular lip 28 at the exit for the joint pin 12 from the rocket, which lip bears against the neck of the joint pin and forms the seal. To provide a better anchorage of the synthetic resin housing in the tubular member 22, the latter is provided with openings 29, which increase in size towards the outside in dovetailed fashion and into which the synthetic resin penetrates when poured. Similar openings can be provided in the cup-shaped plates 26.

To increase the elasticity by providing greater possibilities of flow, annular grooves or recesses can be provided in the inside of the socket.

Fig. 16 shows a ball and socket joint in which the ball end does not possess a smooth surface but is finely corrugated or ribbed, whereby its surface can absorb fouling, such as fine dust particles and the like. The lubricant can also enter the fine corrugations.

Of course, it is also possible to produce an unsmoothed surface having indentations within the scope of the invention in any other way. The indentations may also be provided in the bearing surface of the socket. It is also possible for both the ball and the socket seat to have an indentedsurface. In such a case, too, a surface formation according to the invention may be of advantage if both the socket and the ball itself have surfaces of synthetic resin of greater or lesser elasticity.

The surface formation according to the invention is not limited to ball and socket joints in which the entire joint socket consists of synthetic resin.

I claim:

1. A ball and socket joint comprising a rod-like link member, arms extending from said member and having at least a portion thereof arcuate in shape, the largest cross sectional dimension of said arms being smaller than the largest cross sectional dimension of said member, and a synthetic resin socket member molded about said arms and defining a socket therewithin, said arms being completely encased in said resin.

2. A ball and socket joint as set out in claim 1 wherein said synthetic resin is selected from the group consisting of a polycondensation product of adipic acid and hexamethylene diamine, polyurethane, and a reaction product of glycol polyester and a diisocyanate.

3. A ball and socket joint as set out in claim 1 wherein said arms comprise wire stirrups having ends attached to said member.

4. A ball and socket joint as set out in claim 1 including a ball received in said socket, at least one of the interengaging surfaces of said ball and said socket having fine indentations.

5. A ball and socket joint comprising a rod-like link member, a pair of wire stirrups having ends secured to said link member, said stirrups having at least a portion thereof arcuate in shape and extending in spaced planes, a synthetic resin socket member molded about and completely encasing said stirrups and defining a spherical socket therewithin, said socket member having an opening at one end with a groove formed in said socket member surrounding said opening and an aperture at the opposite end, a plate resting in said groove and closing said opening, a ball rotatably positioned in said spherical socket and having a pin extending therefrom through said aperture, and a pee g sleeve of elastic material surrounding a portion of said socket member and extending to and surrounding said ball pin.

6. A ball and socket joint comprising a rod-like link member having a ring formed integrally therewith at one end thereof, a synthetic resin socket member molded about and completely encasing said ring and defining a spherical socket therewithin, said socket member having an opening at one end with a groove formed in said socket member surrounding said opening and an aperture at the opposite end, a plate resting in said groove and closing said opening, a lining secured to the inner surface of said spherical socket, said lining being formed of synthetic resin more elastic than said socket member, and a metal shell surrounding a portion of said socket member and said rod-like link member.

7. A ball and socket joint comprising a tubular connecting member having opposite portions of its sides expanded outwardly in arcuate shape to define a ring, a pair of cup-shaped plates rigidly secured in said tubular member on opposite sides of said ring, a synthetic resin socket member molded about and substantially completely encasing at least a portion of said ring and molded to both said cup-shaped plates, said socket member defining a spherical socket therewithin, said socket member having an opening at one end with a groove formed in said-socket member surrounding said opening and an aperture at the opposite end, a plate resting in said groove and closing said opening, and a ball rotatably positioned in said spherical socket and having a pin extending therefrom through said aperture.

8. A ball and socket joint comprising a tubular connecting member having opposite portions of its sides expanded outwardly in arcuate shape to define a ring, said opposite portions of said sides having spaced openings formed therein, a first cup-shaped plate rigidly secured in said tubular member on one side of said ring, a second cup-shaped member rigidly secured to and closing the end of said tubular member on the other side of said ring, a synthetic resin socket member molded about and substantially completely encasing at least a portion of said ring and molded in said openings and to said cupshaped plates, said socket member defining a spherical socket therewithin, said socket member having an opening at one end with a groove formed in said socket member surrounding said opening, said socket member having an annular lip extending therefrom forming an aperture at the opposite end, a plate resting in said groove and closing said opening, said spherical socket, said ball having a pin extending .through said aperture and closely surrounded by said annular lip.

References Cited in the file of this patent UNITED STATES PATENTS 1,646,288 Graham Oct. 18, 1927 1,842,747 Crawford et al. 1 Jan. 26, 1932 1,923,601 Weaver Aug. 22, 1933 1,940,258 Lantz Dec. 19, 1933 2,141,791 Keller Dec. 27, 1938 2,246,086 Austin June 17, 1941 2,305,815 Schwarz Dec. 22, 1942 2,333,014 Kennedy Oct. 26, 1943 2,424,914 Brown July 29, 1947 2,791,454 Saives May 7, 1957 a ball rotatably positioned in 

